A photographic optical device which is mounted on a portable apparatus is provided with a movable body including a lens, a lens drive mechanism for magnetically driving the movable body in an optical axis direction, and a photographing unit in which an imaging element is supported on a support body. In the photographic optical device, various types of a hand shake correction mechanism are mounted for restraining disturbances of a photographed image due to a hand shake of a user. As such a shake correction mechanism, a structure where a shake correction lens provided in a photographing unit is shifted in a direction canceling the shake, a structure where an imaging element is shifted in a plane perpendicular to an optical axis, and the like have been practically used.
A structure where a shake correction mechanism is incorporated into a photographing unit is capable of being adopted in a photographic optical device which is mounted on a relatively large portable apparatus such as a digital camera. However, in a photographic optical device which is mounted on a small portable apparatus such as a cell phone with camera, since a photographing unit is smaller, the shake correction mechanism is unable to be incorporated into the photographing unit.
In order to prevent this problem, in a photographic optical device, it has been proposed that a shake correction mechanism is structured between a photographing unit and a fixed body which supports the photographing unit. In a case that this structure is adopted, the photographing unit is structured as a movable module which is capable of displacing in a direction intersecting the optical axis on the fixed body (see Patent Literature 1).
The shake correction mechanism described in Patent Literature 1 is structured so that a photographing unit is elastically urged by a flat spring against a pivot part formed on a fixed body and the photographing unit is capable of displacing with the pivot part as a supporting point. The photographing unit is rocked around an “X”-axis perpendicular to an optical axis by a first photographing unit drive mechanism which is arranged at one side portion displaced from the pivot part, and the photographing unit is rocked around a “Y”-axis perpendicular to the optical axis by a second photographing unit drive mechanism arranged at another one side portion displaced from the pivot part.                [PTL 1] Japanese Patent Laid-Open No. 2007-310084        
However, like the shake correction mechanism described in Patent Literature 1, in a first photographing unit drive mechanism or in a second photographing unit drive mechanism which is arranged at one side portion with respect to the pivot part, even when a positional relationship between the drive mechanism and the pivot part is slightly displaced, a driving power is varied and thus it is difficult to obtain a stable thrust force.
Further, like the shake correction mechanism described in Patent Literature 1, in a structure that a photographing unit drive magnet is provided on a fixed body side and a photographing unit drive coil is provided on a photographing unit side which is a movable body side, since wiring lines for power supply are required to connect with the photographing unit drive coil, the number of wiring lines to the photographing unit is increased and thus a wiring structure is complicated and, on the photographing unit side, it is difficult to increase a winding number of the photographing unit drive coil. Further, since the photographing unit drive coil whose mass is larger than that of the photographing unit drive magnet is provided on the photographing unit side which is the movable body side, a large force is required to rock the photographing unit and its control is difficult
In addition, when a magnetic drive mechanism using a photographing unit drive magnet and a photographing unit drive coil is adopted like the shake correction mechanism described in Patent Literature 1, a magnetic device such as a speaker may be affected due to a magnetic noise emitted from the magnetic drive mechanism to the outside. Further, when a magnetic effect is applied from the outside, shake correction is not performed accurately.
In view of the problems described above, at least an embodiment of the present invention provides an optical unit with shake correcting function in which a structure of the photographing unit drive mechanism for shake correction for a movable module provided with a lens such as a photographing unit is improved to be capable of surely correcting a shake such as a hand shake.
Further, at least an embodiment of the present invention provides an optical unit with shake correcting function in which an arrangement of a magnet and a coil which structure the photographing unit drive mechanism for shake correction to the movable module is improved to be capable of rapidly correcting a shake with less power consumption.
Further, at least an embodiment of the present invention provides an optical unit with shake correcting function in which, even when a magnetic drive mechanism is adopted, a magnetic effect to the outside and a magnetic effect from the outside can be prevented.